RFR: 8274788: Support archived heap objects in ParallelGC

[Ioi Lam]

On Wed, 2 Mar 2022 07:04:28 GMT, Calvin Cheung <ccheung at openjdk.org> wrote:

> With this change when the UseParallelGC is enabled, the CDS archived heap objects could be loaded
> into the PSOldGen during VM bootstrap. This improves startup time since the module graph could be
> loaded from the archive.
> 
> 
> $ perf stat -r 40 -XX:+UseParallelGC -version
> 
> before: 0.069244290 seconds time elapsed            ( +-  0.49% )
> after:    0.058555167 seconds time elapsed          ( +-  0.49% )
> 
> Passed CI tiers 1 - 4 tests.
> 
> Thanks @tschatzl for his help on GC changes.

The CDS and test changes look good to me.

test/hotspot/jtreg/runtime/cds/appcds/TestParallelGCWithCDS.java line 2:

> 1: /*
> 2:  * Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved.

Should be 2022

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Marked as reviewed by iklam (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/7655